Anton graf



(No Model.)

A. GRAP.

. FURNACE 130012.. No. 485,189. Patented Nov. 1, 1892.

UNITED STATES PATENT OFFICE.

ANTON GRAF, OF GEORGETOWN, MASSACHUSETTS, ASSIGNOR OF ONE HALF TOSTEPHEN OSGOOD, OF SAME PLACE.

FURNACE-DOOR.

SPECIFICATION forming part of Letters Patent No. 485,189, dated November1,1892.

Application filed May 2,1892. Serial No. 431,473- (No model.)

To all whom it may concern:

Be it known that I, ANTON GRAF, of Georgetown, in the county of Essex,State of Massachusetts, have invented certain new and usefulImprovements in Furnace-Doors, of which the following is a descriptionsufficiently full, clear, and exact to enable any person skilled in theart or science to which said invention appertains to make and use thesame, reference being had to the accompanying drawings, forming part ofthis specification, in which- Figure 1 is a sectional view showing thedoor and wall of a furnace fire-box; and Fig. 2, an elevation of theinner face of the door, showing my improved insulating device.

Like letters of reference indicate corresponding parts in both thefigures of the drawlngs.

My invention relates especially to an attachment for protecting thedoors of furnace fireboxes from heat, so that they may be readilymanipulated, it being particularly designed for use with furnaces inwhich gas or other fuel producing intense heat is employed.

The nature and operation of the improvement will be readily understoodby all conversant with such matters from the following explanation.

The metallic door A (shown in the drawings) is of ordinary constructionand mounted in the usual manner on the fire-box wall B. Supporting-arms15, comprising bolts fitted to receive nuts '0, project horizontallyfrom the inner face of the door. Short sleeves w, preferably ofinsulating material, are disposed on A rectangular box 0, of thin sheetthe bolts.

metal, open at its top 00 and slightly less in width than the opening yin the wall 13, is mounted on the inner ends of the bolt-arms t, whichpass therethrongh. The box is held out of contact with the door by thesleeves to and is secured on the bolts by the nuts o. Said 'box isfilled with infusorial earth, asbestus, or

any suitable non-heat-conduoting material 2. By this arrangement ofparts an air space or chamber M is left between the door A andinsulating-box O. The heat radiating directly from the fire strikes thebox 0, which con tains the non-heat conductor.

The air in the space on is maintained at a temperature much lower thanin the box, and comparatively-little heat is absorbed by the metal door,which may thus be manipulated by the fireman without discomfort.

Having thus explained my invention, what I claim is 1. A furnace-doorhaving a box connected therewith by bolts, said box being filled withinsulating material, leaving an air-space between said door and box, andinsulating material on the bolts between the door and box.

2. A furnace-door having a box connected therewith by bolts, said boxbeing open at the top and filled with insulating material and leaving anair-space between said box and door, and insulating-sleeves on the boltsbetween the door and box.

ANTON GRAB.

Witnesses:

ORLANDO B. TENNEY, JOHN A. PEABODY.

